The present invention relates generally to electronic packaging technology and, more particularly, to electronic packaging technology applicable to power modules, such as ac-ac, ac-dc and dc-ac converters and electronic switches.
Typical power module designs employ wire bonds for connecting power devices to power busses and control terminals. The power devices are commonly soldered onto a metalized insulating ceramic substrate, often beryllium oxide or aluminum nitride metalized with a conductive metal such as copper or aluminum, and subsequently bonded to a massive copper heat spreader. Typically, an injection molded polymer shell covers the module, exposing only the input/output and control terminals and the copper heat spreader. The heat spreader is attached to a heat sink, such as extruded aluminum fins or a cold plate, for example. Thermal contact between the heat spreader and the heat sink is achieved through a thermal paste or a thermally conductive polymer.
Disadvantages of presently available power module designs such as those described hereinabove include relatively high parasitic impedance, high volume and weight, high thermal resistance, and limited reliability primarily due to wire bonds. Accordingly, it would be desirable to provide power electronic module packaging technology that overcomes such disadvantages.